Shortest Addition Chains

[Alec Mihailovs]

From: "Alec Mihailovs" <alec at mihailovs.com>
> 
> The shortest chain has length 18. Here it is: 
> 
> 1+1=2, 2+1=3, 3+3=6, 6+6=12, 12+12=24, 24+3=27, 27+27=54, 
> 54+54=108, 108+108=216, 216+1=217, 217+217=434, 
> 434+434=868, 868+868=1736, 1736+1736=3472, 
> 3472+3472=6944, 6944+6944=13888, 13888+3=13891, 
> 13891+13891=27782

Sorry, I didn't see Max A. earlier replies when I sent that. 

Max A.> 1, 2, 3, 6, 12, 24, 48, 96, 192, 384, 386, 772, 1544, 
Max A.> 3088, 3472, 6944, 13888, 13891, 27782

The chain is different though. Still contains 3 (a few times).

Alec